I have just recently did a thumb stick swap on the controller, and now the LT/RT triggers stopped working. I have...

This might seem absolutely crazy, but double, triple, idk check the power source again. Yes, again. If that is not the problem, it could very well be the power supply, so I’d suggest replacing that.

This seems like a bad drive, which has happened to 2/3 of my OG Xboxes. If the console is modded, try going to their troubleshooting page to see what might be wrong. If not, try replacing the IDE cable. If the drive is not getting power, try replacing the drive power cable. From what I have experienced, you might be screwed. There could be a problem with the DVD drive motherboard or console motherboard as well, maybe from a un-removed clock capacitor.

I don’t have a lot of experience with the Series X/S line, but from what is the same across the One X/S which I repair a lot, this could be a motherboard problem, such as a compactor exploding/leaking, broken soldier joints, etc. Try looking up possible motherboard weak points if that helps in any way.

You might be able to use some cheap replacement ones off of Amazon like this one: https://www.amazon.com/Pdflie-Replacement-Worktunes-Protector-Headphones/dp/B0CJ4GS17Q/ref=sr_1_5?crid...-t9ax4W0uHDrRpL9iuTogZQTOT5Yke4FzKFEflTtw...-Pj6fup3VHJYbD4TJ3iy07osC5_pMfJoyfrHBoKMp...-m7Q7fPfx53VrBnSsyUb1Ii9_JKs.ha3mkwDK3li2...-5 If those don’t work, sometimes they have adhesion put on them to stay in place, try cleaning that off. It could also be that the headphones were made to be unrepairable, in that case idk what you should do.